Converting Solar Power Units: Megawatt To Kilowatt

When you hear about a new solar farm being constructed in your area, your eyes may glaze over when you hear some of the complicated technical details. The size of solar energy projects is commonly measured in kilowatts or megawatts, but it can seem hard to process this information without knowledge about home energy use.

Let’s demystify the topic of megawatts and kilowatts, which are common metrics for electrical energy.

What Are The Units For Solar Power?

Watts (W), kilowatts (kW), megawatts (MW) and gigawatts (GW) are a measurement of electricity and also the unit of power for solar energy output. Watts can be calculated by multiplying voltage (V) x current (I). Therefore, W = V x I. You might remember this formula from a physics class – it’s called Ohm’s Law.

Most of the electrical loads in your home are also measured in watts or kilowatts. For example, a fan may use about 20 watts on a low setting and 35 watts on high. Your fridge might use about 200 watts while it runs, but it cycles on and off during the day. Something like a water heater may consume thousands of watts of power when operating.

What Is A Kilowatt?

Watts are a common measurement of a relatively small amount of power, and a kilowatt (kW) is a term for 1,000 watts. Often, units of power are measured in kilowatt-hours (kWh), which are a measure of electricity over a set amount of time. Note the difference between kW versus kWh.

As an example, a small toaster oven might use about 1,000 watts or 1 kilowatt of power per hour. If you run the unit for one hour,  it would consume 1 kWh of electricity. Most residential power bills are measured in kWh, and the average household consumes nearly 900 kWh of electricity monthly.

What Is A Megawatt?

The next unit of power after a kilowatt is a megawatt (MW), which is 1 million watts of electricity or 1,000 kilowatts. Again, if the unit has “hours” at the end, it measures total electricity use in one hour. 

A small solar farm might produce 1 megawatt hour (MWh) of solar electricity in one hour if the solar panels are generating 1 MW continuously.

How To Convert Megawatts To Kilowatts

Because 1,000 kW = 1 MW, you simply multiply MW by 1,000 to get kW. Therefore kWh = mWh x 1,000. The same applies to converting MWh and kWh.

So, if you have a solar panel system, it might produce 1 mWh per month on average.  If you want to convert this output to kWh, it is 1 mWh x 1,000 = 1,000 kWh.

However, the output of solar panels declines later in the day, shortly before sunset, which is something you’ll have to take into consideration. Let’s say the solar farm produced 0.5 mWh at that time. Therefore, at this time, your output may only be 0.5 mWh x 1,000 = 500 kWh.

Megawatts To Kilowatts Conversion Table 

The following table highlights how you would convert mWh to kWh, with specific examples.

The Bottom Line

Although our power bills use kWh, many homeowners are unfamiliar with exactly how various units of electricity are measured. Knowing how to convert kW to MW helps us demystify these units of electricity and understand how they’re used.

This is helpful if you are trying to determine how many solar panels you will need to power your home. A Rocket Solar^SM expert can walk you through every step of this process.